Vacuum processing apparatuses that perform various kinds of substrate processing under vacuum, such as film formation and etching, are widely used. As shown in Patent Document 1, shields are provided on an inner wall of a vacuum processing apparatus to prevent a film-forming substance which is also deposited on a portion other than a substrate during film formation or an etching substance dispersed during etching (these substances are also collectively referred to simply as deposits hereinbelow) from being attached to the inner wall of a chamber. A substrate processing space (also referred to simply as a processing space) should desirably be surrounded by the shields as thoroughly as possible so as not to cause deposits on the inner wall of the chamber.
When the processing space is surrounded by the shields, as shown in Patent Document 1, a gas introduced into the processing space is exhausted to the outside of the processing space through a gap between the shields or between the shield and another member.
Further, Patent Document 2 proposes that the shields are configured such that in a chamber, a shield space, which is formed by the shields, has a film-formation space surrounding a substrate holder and a movable-plate housing space in which a movable plate can be housed, and that two exhaust channels are provided for exhausting a gas from the shield space. Of these exhaust channels, a first exhaust channel is a gap provided between the substrate holder and the shield, and a second exhaust channel is an opening portion provided in the movable-plate housing space. The movable plate is movable between a position where the movable plate closes the opening portion (some clearance may exist between the movable place and the shield) and a position where the movable plate allows the opening portion so be open. When the movable plate is at the closing position, a gas introduced into the shield space is exhausted mostly from the gap, allowing a uniform film formation process on a surface of the substrate placed on the substrate holder. When the movable plate is at the opening position, exhaust conductance in the shield space is drastically increased compared to a state where the movable plate is at the closing position, and consequently, residual gas in the shield space can be exhausted efficiently.